For new contributors, the following are useful onboarding information.
Work within Neutron is discussed on the openstack-dev mailing list, as well as in the #openstack-neutron IRC channel. While these are great channels for engaging Neutron, the bulk of discussion of patches and code happens in gerrit itself.
With regards to gerrit, code reviews are a great way to learn about the project. There is also a list of low or wishlist priority bugs which are ideal for a new contributor to take on. If you haven’t done so you should setup a Neutron development environment so you can actually run the code. Devstack is the usual convenient environment to setup such an environment. See devstack.org or NeutronDevstack for more information on using Neutron with devstack.
Helping with documentation can also be a useful first step for a newcomer. Here is a list of documentation bugs that are tagged with ‘neutron’; bug reports are created here for neutron reviews with a ‘DocImpact’ in the commit message.
The main IRC channel for Neutron is #openstack-neutron. We also utilize #openstack-lbaas for LBaaS specific discussions. The weekly meeting is documented in the list of meetings wiki page.